I am a Pastafarian, but can understand how a person who is convinced that I will burn in everlasting hell for that choice might feel compelled to help me avoid that fate.
I mean seriously, how could someone who really (really) believes people like me will suffer eternal damnation not make some small effort on our behalf? To do otherwise would be like watching man drown if he does not specifically ask that you to toss the life preserver at your feet.
Not a bad thing to meet and interact with wide variety of people and characters on Thru Hike. Sort of like college, in that regard. The important thing is not if they are right or wrong, but rather that they are sincere.
That will come through right away -- and who knows, the pastor might even take away a better understanding of he Church of the Flying Spaghetti Monster as he meets all kinds of hikers himself.